CN113745266A

CN113745266A - Display device

Info

Publication number: CN113745266A
Application number: CN202110994985.4A
Authority: CN
Inventors: 张延任; 王彦凯
Original assignee: AU Optronics Corp
Current assignee: AU Optronics Corp
Priority date: 2021-02-09
Filing date: 2021-08-27
Publication date: 2021-12-03
Anticipated expiration: 2041-08-27
Also published as: TWI760105B; TW202232786A; CN113745266B

Abstract

The invention discloses a display device which comprises a substrate, a plurality of scanning lines, a plurality of data lines, a plurality of light-emitting elements, a first antireflection layer and a second antireflection layer. The scan lines and the data lines extend along a first direction and a second direction, respectively. The light emitting element is surrounded by the scan line and the data line. The first antireflection layer covers the scanning lines and the data lines and is provided with a plurality of openings, wherein the plurality of openings expose the light-emitting elements. In a top view of the display device, the second antireflection layer overlaps at least the first antireflection layer. The light emitting element emits light at a wavelength different from the absorption wavelength of the second antireflection layer. The absorption wavelength of the first antireflection layer is different from the absorption wavelength of the second antireflection layer.

Description

Display device

Technical Field

The present invention relates to a display device, and more particularly, to a display device having at least two reflection reducing layers.

Background

Micro-Light Emitting diodes (mleds) have advantages such as long lifetime, small size, high shock resistance, low heat generation, and low power consumption, and are also currently used in flat panel and small-sized display devices. At present, metal wiring in a display panel adopting a micro light-emitting diode is exposed and is not shielded, so that the problem of high reflectivity of the display panel is easily caused.

The general solutions are for example: performing Anti-reflection surface treatment (Anti-reflection surface treatment) to form an Anti-reflection film on the display panel, so as to reduce the reflectivity by about 4%; or, a circular polarizer (circular polarizer) is disposed on the display panel, although the reflectivity can be reduced by about 95%, the circular polarizer will block the region where the light emitting device is disposed (i.e. the light emitting region of the display panel), so that the transmittance of the display panel is reduced by about 60%; or, a Black Matrix (BM) is formed on the metal trace, but the current process for forming the BM is limited by the process capability and cannot completely cover the metal trace in a large area, and if a circular polarizer is used to shield the exposed metal trace, the transmittance of the display panel is still reduced by about 60%. Therefore, it is a challenge for researchers in this field to design a display device with both low reflectivity and high transmittance.

Disclosure of Invention

The invention provides a display device, which is designed to be beneficial to reducing the reflectivity, simultaneously avoiding the reduction of the transmittance and maintaining excellent color characteristics such as hue and the like, and further improving the display effect of the display device.

At least one embodiment of the invention provides a display device, which includes a substrate, a plurality of scan lines, a plurality of data lines, a plurality of light emitting elements, a first antireflection layer, and a second antireflection layer. The scanning line is configured on the substrate and extends along a first direction. The data line is configured on the substrate and extends along a second direction, wherein the first direction is intersected with the second direction. The light emitting element array is arranged on the substrate. Each light-emitting element is surrounded by two adjacent scanning lines and two adjacent data lines, and the light-emitting element is electrically connected with one of the scanning lines and one of the data lines. The first antireflection layer covers the plurality of scanning lines and the plurality of data lines and is provided with a plurality of openings, wherein the openings expose the light-emitting elements. The second antireflection layer is arranged on the substrate. In a top view of the display device, the second antireflection layer overlaps at least the first antireflection layer. The light-emitting element has a light-emitting wavelength different from an absorption wavelength of the second antireflection layer, and the absorption wavelength of the first antireflection layer is different from an absorption wavelength of the second antireflection layer.

In an embodiment of the invention, a color of the first antireflection layer includes brown, and a color of the second antireflection layer includes blue.

In an embodiment of the invention, the chromaticity coordinates (x, y) of the reflected light reflected by the first antireflection layer satisfy the following formula (1) and formula (2) under the condition of the light source D65:

0.350 ≦ x ≦ 0.400 formula (1)

0.350 ≦ y ≦ 0.400 formula (2).

In an embodiment of the invention, the CIE chromaticity coordinates (x, y) of the reflected light reflected by the first antireflection layer and transmitted through the second antireflection layer satisfy the following formulas (3) and (4) under the condition of the D65 light source:

0.280 ≦ x ≦ 0.350 equation (3)

0.280 ≦ y ≦ 0.350 equation (4).

In an embodiment of the invention, the absorption wavelength of the second antireflection layer is 590nm to 600nm, and the light transmittance of the second antireflection layer at a wavelength of 590nm to 600nm is 0.30 or less.

In an embodiment of the invention, the second antireflection layer entirely covers the substrate.

In an embodiment of the invention, the second antireflection layer includes a planarization layer and an absorption layer. The flat layer is arranged on the substrate and covers the first antireflection layer and the light-emitting element. The absorption layer is disposed on the planarization layer. In a top view of the display device, the absorbing layer overlaps at least the first antireflection layer.

In an embodiment of the invention, the second antireflection layer includes a planarization layer and absorption particles. The flat layer is arranged on the substrate and covers the first antireflection layer and the light-emitting element. The absorbing particles are dispersed in the planarization layer.

In an embodiment of the invention, the first antireflection layer includes a first dielectric layer, a photoresist layer and a second dielectric layer in sequence from the substrate side, and the second dielectric layer conformally covers the photoresist layer.

In an embodiment of the invention, the first dielectric layer and the second dielectric layer are made of silicon nitride, and the photoresist layer is made of positive photoresist.

In an embodiment of the invention, the display device further includes a plurality of pad patterns. The pad pattern array is arranged on the substrate and electrically connected with the light emitting element. One of the openings of the first anti-reflection layer exposes at least one pad pattern, wherein a distance between a sidewall of the one of the openings extending along the second direction and a side surface of the exposed pad pattern extending along the second direction is about 10 ± 3% μm.

Based on the above, the first antireflection layer is arranged to shield the large-area signal lines, so as to reduce the reflectivity caused by the exposure of the signal lines of the display device. In addition, the second reflection reducing layer with the absorption wavelength different from that of the first reflection reducing layer is covered on the first reflection reducing layer, so that the reflected light reflected by the first reflection reducing layer can be converted into the reflected light with the hue close to the natural light after penetrating through the second reflection reducing layer, and the display device has low reflectivity and can also present the display effect with excellent color characteristics such as hue and the like. In addition, the absorption wavelength of the second antireflection layer is different from the light-emitting wavelength of the light-emitting element, so that even if the second antireflection layer shields the light-emitting element, the light transmittance of the light-emitting element can be prevented from being reduced.

In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanied with figures are described in detail below.

Drawings

Fig. 1A to 1C are schematic top views of a display device according to an embodiment of the invention.

FIG. 2 is a schematic diagram of one embodiment of a cross section along section line A-A' in the display device of FIG. 1C.

FIG. 3 is a schematic view of another embodiment of a cross section along the cross-sectional line A-A' in the display device of FIG. 1C.

Fig. 4A to 4C are spectral diagrams (spectra) according to an embodiment of the invention.

Fig. 5 is a schematic diagram illustrating changes in transmittance and reflectance according to an embodiment of the invention.

Wherein, the reference numbers:

10. 10A, 10B display device

100 substrate

110 driving element

112 channel layer

114 ohmic contact layer

116 insulating layer

200 light emitting element

200a top surface

200b side surface

300 first antireflection layer

302 first dielectric layer

304 photoresist layer

306 second dielectric layer

400. 400A, 400B a second antireflection layer

410 flat layer

410a surface

420 absorbing layer

430 absorbing particles

B blue light emitting element

BP pattern of bonding pad

D1 first direction

D2 second direction

DE drain electrode

DL, DL1, DL2, DL3 data line

G green light emitting element

GE grid electrode

GI gate insulation layer

GL scanning line

LA light emitting area

O1 first opening

O2 second opening

PV1, PV2 passivation layer

R red light emitting element

SE source

TH through hole

Detailed Description

In the drawings, the thickness of layers, films, panels, regions, etc. have been exaggerated for clarity. Like reference numerals refer to like elements throughout the specification. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "connected to" or "overlapping" another element, it can be directly on or connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element, there are no intervening elements present. As used herein, "connected" may refer to physical and/or electrical connections. Further, "electrically connected" or "coupled" may mean that there are additional elements between the two elements.

It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a "first element," "component," "region," "layer," or "portion" discussed below could be termed a second element, component, region, layer, or portion without departing from the teachings herein.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms, including "at least one", unless the content clearly indicates otherwise. "or" means "and/or". As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions integers, steps, operations, elements, components, and/or groups thereof.

Furthermore, relative terms, such as "lower" or "bottom" and "upper" or "top," may be used herein to describe one element's relationship to another element, as illustrated. It will be understood that relative terms are intended to encompass different orientations of the device in addition to the orientation depicted in the figures. For example, if the device in one of the figures is turned over, elements described as being on the "lower" side of other elements would then be oriented on "upper" sides of the other elements. Thus, the exemplary term "lower" can include both an orientation of "lower" and "upper," depending on the particular orientation of the figure. Similarly, if the device in one of the figures is turned over, elements described as "below" or "beneath" other elements would then be oriented "above" the other elements. Thus, the exemplary terms "lower" or "upper" may include both an orientation of above and below.

As used herein, "about" or "substantially" includes the stated value and the average value within an acceptable range of deviation of the specified value as determined by one of ordinary skill in the art, taking into account the measurement in question and the specified amount of error associated with the measurement (i.e., the limitations of the measurement system). For example, "about" may mean within one or more standard deviations of the stated value, or within ± 30%, ± 20%, ± 10%, ± 5%. Further, as used herein, "about" or "substantially" may be selected based on optical properties, etch properties, or other properties, with a more acceptable range of deviation or standard deviation, and not all properties may be applied with one standard deviation.

Unless defined otherwise, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present invention and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Exemplary embodiments are described herein with reference to cross-sectional views that are schematic illustrations of idealized embodiments. Thus, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, the embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region shown or described as flat may generally have rough and/or nonlinear features. Further, the acute angles shown may be rounded. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the claims.

Fig. 1A to 1C are schematic top views of a display device according to an embodiment of the invention. For convenience of illustration, the positions of the first antireflection layer and the second antireflection layer are omitted in fig. 1A; the position of the second antireflection layer is omitted in fig. 1B.

Referring to fig. 1A to 1C, the display device 10 includes a substrate 100, a plurality of scan lines GL, a plurality of data lines DL, a plurality of light emitting elements 200, a first anti-reflective layer 300, and a second anti-reflective layer 400. In the embodiment, the material of the substrate 100 may be glass, quartz, organic polymer, or other applicable materials, but the invention is not limited thereto. The scanning line GL is disposed on the substrate 100 and extends along the first direction D1. The data line DL is disposed on the substrate 100 and extends along a second direction D2 intersecting the first direction D1.

Referring to fig. 1A, a plurality of light emitting devices 200 are arranged in an array on a substrate 100. In other words, the light emitting elements 200 may be arrayed along the first direction D1 and the second direction D2, wherein the first direction D1 may be understood as a transverse direction and the second direction D2 may be understood as a longitudinal direction. Therefore, the lateral direction and the longitudinal direction described in the following embodiments can be regarded as the first direction D1 and the second direction D2 in fig. 1A, respectively. In the present embodiment, each light emitting device 200 is surrounded by two adjacent scan lines GL and two adjacent data lines DL. For example, the light emitting elements 200 aligned in a line along the first direction D1 are sandwiched between two scanning lines GL; the light emitting elements 200 aligned in a row along the second direction D2 are sandwiched between the two data lines DL. Therefore, the light emitting elements 200 in the same row and the light emitting elements 200 in the same column described in the following embodiments can be regarded as the light emitting elements 200 arranged along the first direction D1 and the light emitting elements 200 arranged along the second direction D2 in fig. 1A, respectively. In an embodiment, the light emitting device 200 is, for example, a micro light emitting diode (mLED), but the invention is not limited thereto.

In this embodiment, the display device 10 further includes a plurality of driving elements 110 and a plurality of pad patterns BP. As shown in fig. 1A, the driving element 110 is disposed on the scanning lines GL, and the driving element 110 is electrically connected to one of the scanning lines GL and one of the data lines DL, respectively. The pad patterns BP are arranged in an array on the substrate 100. In the embodiment, every two pad patterns BP are surrounded by two adjacent scan lines GL and two adjacent data lines DL, and the pad patterns BP are electrically connected to the light emitting device 200. In addition, one of the two pad patterns BP is electrically connected to the driving element 110. That is, the light emitting device 200 is electrically connected to the corresponding scan line GL and the data line DL via the pad pattern BP and the driving device 110. In the present embodiment, the light emitting devices 200 arranged in the same row along the first direction D1 can be electrically connected to the same scanning line GL respectively. For example, the light emitting devices 200 in the same row may be electrically connected to the scan lines GL on the same side (e.g., the upper side of fig. 1A) through the pad patterns BP and the driving devices 110, but the invention is not limited thereto. On the other hand, the light emitting elements 200 arranged in the same row along the second direction D2 can be electrically connected to the data lines DL on the same side. For example, the light emitting devices 200 in the same row may be electrically connected to the data lines DL located on the same side (e.g., the left side of fig. 1A) through the pad patterns BP and the driving device 110, but the invention is not limited thereto. It should be noted that although fig. 1A to 1C illustrate that each light emitting device 200 is electrically connected to two pad patterns BP, those skilled in the art can adjust the number and connection relationship of the pad patterns BP according to design requirements, and the invention is not limited thereto. In an embodiment, the material of the pad pattern BP may be a conductive material such as a metal.

In some embodiments, the plurality of light emitting elements 200 may include a plurality of red light emitting elements R, a plurality of green light emitting elements G, and a plurality of blue light emitting elements B respectively arranged along the second direction D2. For example, taking the data line DL1 shown in fig. 1A as an example, the data line DL1 may be electrically connected to the same row of red light-emitting elements R; taking the data line DL2 shown in fig. 1A as an example, the data line DL2 can be electrically connected to the green light emitting elements G in the same row; taking the data line DL3 shown in fig. 1A as an example, the data line DL3 can be electrically connected to the same row of blue light emitting elements B, and one skilled in the art can adjust the arrangement and connection relationship of the data line DL and the light emitting elements 200 according to design requirements, which is not limited by the invention.

In the present embodiment, the pad pattern BP and the data line DL may be electrically connected to the drain and the source on two opposite sides of the active layer of the driving device 110, respectively. For example, the driving device 110 may be a transistor having a gate electrode connected to one of the scan lines GL, a source electrode connected to one of the data lines DL, and a drain electrode connected to the pad pattern BP. In addition, in order to avoid short circuit between the scan line GL and the data line DL, the scan line GL and the data line DL may be formed of different films, and one or more insulating layers may be interposed between the scan line GL and the data line DL.

Referring to fig. 1B, the first antireflection layer 300 at least covers the scan lines GL, the data lines DL and the driving elements 110. In one embodiment, the area ratio of the regions surrounded by two adjacent scanning lines GL and two adjacent data lines DL is set to 100%, the area ratio occupied by the first antireflection layer 300 is, for example, 70% to 95%, and the area ratio occupied by the light emitting elements 200 is, for example, 5% or less. In the embodiment, the first antireflection layer 300 has a plurality of first openings O1, and the first opening O1 exposes the light emitting device 200 and the pad pattern BP without exposing the scan line GL, the data line DL and the driving device 110. In one embodiment, the distance between a sidewall of the first opening O1 extending along the second direction D2 and a side of the exposed pad pattern BP extending along the second direction D2 is about 10 ± 3% μm. In this way, the first antireflection layer 300 can be prevented from blocking the region where the light emitting element 200 is disposed (hereinafter, referred to as the light emitting region LA, as shown in fig. 1C), so as to ensure the light emitting area of the display device 10.

Referring to fig. 1C, the second antireflection layer 400 is disposed on the substrate 100. As shown in fig. 1C, the second antireflection layer 400 overlaps at least the first antireflection layer 300. In this way, the reflected light reflected by the first reflection reducing layer 300 can pass through the second reflection reducing layer 400, so as to adjust the color phase presented by the reflected light. In the embodiment, the second antireflection layer 400 is, for example, entirely covered on the substrate 100, but the invention is not limited thereto as long as the reflected light reflected by the first antireflection layer 300 can pass through the second antireflection layer 400.

In the present embodiment, the light emitting wavelength of the light emitting device 200 is different from the absorption wavelength of the second antireflection layer 400, so that even if the light emitting device 200 is shielded by the second antireflection layer 400, the light transmittance of the light emitting device 200 can be prevented from decreasing, which will be described in detail later. In addition, the absorption wavelength of the first antireflection layer 300 is different from that of the second antireflection layer 400. For example, the color of the first antireflection layer 300 includes brown, and the color of the second antireflection layer 400 includes bluish. The second antireflection layer 400 has an absorption wavelength of, for example, about 590nm to about 600nm, and the second antireflection layer 400 has a transmittance of, for example, 0.30 or less at a transmitted light wavelength of about 590nm to about 600 nm. Accordingly, the CIE chromaticity coordinates (x, y) of the reflected light reflected by the first antireflection layer 300 under the condition of the D65 light source may satisfy the following equations (1) and (2):

0.350 ≦ x ≦ 0.400 formula (1)

0.350 ≦ y ≦ 0.400 formula (2).

Moreover, the CIE chromaticity coordinates (x, y) of the reflected light reflected by the first retro-reflective layer 300 and transmitted through the second retro-reflective layer 400 under the condition of the D65 light source may satisfy the following formulas (3) and (4):

0.280 ≦ x ≦ 0.350 equation (3)

0.280 ≦ y ≦ 0.350 equation (4).

That is, the display device 10 of the present embodiment utilizes the brown first antireflection layer 300 to shield large-area signal lines (i.e., conductive lines such as the scan lines GL and the data lines DL) to reduce the reflectivity caused by the signal lines of the display device 10 being exposed. In addition, the second retro-reflective layer 400 with a bluish color is used to cover the first retro-reflective layer 300, so that the brown reflected light reflected by the first retro-reflective layer 300 can be converted into reflected light with a hue close to that of natural light (i.e., a Correlated Color Temperature (CCT) of about 5000K to 6000K) after passing through the second retro-reflective layer 400, and thus the display device 10 has a low reflectance and can also exhibit a display effect with excellent color characteristics such as hue.

Hereinafter, embodiments applicable to the first antireflection layer and the second antireflection layer in the above embodiments will be described by way of example, but the present invention is not limited to the embodiments described below.

FIG. 2 is a schematic diagram of one embodiment of a cross section along section line A-A' in the display device of FIG. 1C. It should be noted that fig. 2 follows the element numbers and part of the contents of the embodiment shown in fig. 1A to 1C, wherein the same or similar elements are denoted by the same or similar reference numbers, and the description of the same technical contents is omitted. For the description of the omitted parts, reference may be made to the foregoing embodiments, which are not repeated herein.

Referring to fig. 2, in the display device 10A, the light emitting element 200 and the first antireflection layer 300 are, for example, located on the same film layer, and the film layer where the driving element 110 is located may be between the film layer where the first antireflection layer 300 is located and the substrate 100. As shown in fig. 2, the driving element 110 includes a gate electrode GE, a gate insulating layer GI, a channel layer 112, an ohmic contact layer 114, a source electrode SE, and a drain electrode DE. In the present embodiment, the gate electrode GE is formed on the substrate 100, and the material of the gate electrode GE may be a conductive material. The gate insulating layer GI covers the gate GE and a portion of the substrate 100. The channel layer 112 is formed on the gate insulating layer GI to provide a channel for electron transmission, and the material of the channel layer 112 includes an appropriate material such as amorphous silicon. The ohmic contact layer 114 covers a portion of the channel layer 112 to reduce the resistance between the source electrode SE and the channel layer 112 and between the drain electrode DE and the channel layer 112. As shown in fig. 2, the source electrode SE and the drain electrode DE are disposed on the ohmic contact layer 114. The material of the ohmic contact layer 114 may be N-type doped amorphous silicon. It should be noted that the driving element 110 is illustrated by using a bottom gate thin film transistor (bottom gate TFT), but the invention is not limited thereto. According to other embodiments, the driving element 110 may also be a top gate thin film transistor (top gate TFT) or other suitable thin film transistors.

In the present embodiment, the display device 10A further includes a passivation layer PV1, an insulating layer 116, and a passivation layer PV 2. For example, the passivation layer PV1 is conformally formed on the driving element 110. The insulating layer 116 is blanket covered on the passivation layer PV 1. The passivation layer PV1 and the insulating layer 116 may have a through hole TH therein, wherein the through hole TH exposes a portion of the drain electrode DE, for example. The passivation layer PV2 conformally covers the sidewalls of the through holes TH and the surface of the insulating layer 116. One of the pad patterns BP fills the through hole TH and covers a portion of the passivation layer PV 2. Accordingly, the pad pattern BP may contact the drain electrode DE of the driving element 110 through the through hole TH.

In the present embodiment, the first antireflection layer 300 may have a single-layer structure or a multi-layer structure. In the present embodiment, the first antireflection layer 300 is, for example, a three-layer structure. For example, the first anti-reflective layer 300 includes, in order from bottom to top, a first dielectric layer 302, a photoresist layer 304, and a second dielectric layer 306. The first dielectric layer 302 covers a portion of the passivation layer PV2 and the pad patterns BP, and fills a gap between two adjacent pad patterns BP. For example, the first dielectric layer 302 has a plurality of second openings O2, the second openings O2 expose a portion of the pad pattern BP, and the light emitting device 200 contacts the pad pattern BP through the second openings O2. Accordingly, the light emitting device 200 can be electrically connected to the drain DE of the driving device 110 through the pad pattern BP. In the present embodiment, the second dielectric layer 306 conformally covers the photoresist layer 304. Thus, the first dielectric layer 302 and the second dielectric layer 306 are disposed on the upper and lower sides of the photoresist layer 304, and the interference effect generated by the first dielectric layer 302 and the second dielectric layer 306 can help to reduce the reflectivity of the display device 10A and correct the color shift of the display device 10A, so as to further optimize the display effect of the display device 10A. In addition, the first dielectric layer 302 and the second dielectric layer 306 can also be used as a protection layer to protect the photoresist layer 304. In one embodiment, the first dielectricThe thickness of the layer 302 and the second dielectric layer 306 is, for example, as

The thickness of the photoresist layer 304 is, for example, 2.0 μm to 3.0. mu.m. In one embodiment, the material of the first dielectric layer 302 and the second dielectric layer 306 may be silicon nitride. The material of the photoresist layer 304 may be a positive photoresist. Thus, the process margin for forming the first antireflection layer 300 can be increased, and the first antireflection layer can completely cover the metal wiring or the signal line in a large area.

In the present embodiment, the second antireflection layer 400A includes a planarization layer 410 and an absorption layer 420. The planarization layer 410 is disposed on the substrate 100, and covers the first antireflection layer 300 and the light emitting device 200. The absorption layer 420 is disposed on the planarization layer 410, for example. For example, the planarization layer 410 may fill the space between the first antireflection layer 300 and the light emitting device 200 and cover the top surface 200a and the side surface 200b of the light emitting device 200, so that the absorption layer 420 may be disposed on the planarization surface formed by the planarization layer 410. In one embodiment, a substrate (not shown) is disposed between the absorption layer 420 and the planarization layer 410, so as to ensure that the absorption layer 420 is flatly disposed on the planarization layer 410. In one embodiment, the thickness of the planarization layer 410 is, for example, 50 μm to 150 μm. The thickness of the absorption layer 420 is, for example, 2.5 μm to 3 μm.

As shown in fig. 2, the absorption layer 420 covers, for example, the surface 410a of the planarization layer 410 entirely. In other embodiments, the absorption layer 420 may cover only a portion of the surface 410a of the planarization layer 410, as long as the reflected light reflected by the first reflection reducing layer 300 can pass through the absorption layer 420. For example, the absorption layer 420 may only overlap with the first antireflection layer 300 (not shown) in the top view direction of the display device 10A, but the invention is not limited thereto. In this way, the reflected light reflected by the first antireflection layer 300 can pass through the absorption layer 420, so as to adjust the color phase presented by the reflected light.

FIG. 3 is a schematic view of another embodiment of a cross section along the cross-sectional line A-A' in the display device of FIG. 1C. It should be noted that fig. 3 uses the element numbers and part of the contents of the embodiment of fig. 2, wherein the same or similar element numbers are used to indicate the same or similar elements, and the description of the same technical contents is omitted. For the description of the omitted parts, reference may be made to the foregoing embodiments, which are not repeated herein.

Referring to fig. 3, a difference between the display device 10B of the present embodiment and the display device 10A shown in fig. 2 is that the second antireflection layer 400B includes a planarization layer 410 and absorbing particles 430. In the present embodiment, the absorbing particles 430 are dispersed in the planarization layer 410, for example. For example, the method of forming the second antireflection layer 400B includes the following steps. The material (e.g., gel, etc.) used to form the planarization layer 410 is first mixed with the absorbing particles 430. Then, the mixture is coated on the first antireflection layer 300 and the light emitting device 200, so that the second antireflection layer 400B is blanket formed on the first antireflection layer 300 and the light emitting device 200. In this way, the light emitting device 200 can be fixed by the planarization layer 410, and the absorption particles 430 dispersed in the planarization layer 410 can be used to adjust the color of the reflected light reflected by the first antireflection layer 300. Therefore, the second antireflection layer 400B can reduce the reflectance and exhibit excellent color characteristics such as color while securing the light emitting element 200 and forming a planarized surface.

Hereinafter, the characteristics of the display device according to an embodiment of the present invention, such as absorption spectrum, reflectance, and transmittance, will be analyzed.

Fig. 4A to 4C are spectral diagrams according to an embodiment of the invention.

Referring to fig. 4A, the spectrum diagram shown in fig. 4A is suitable for a display device having only the first antireflection layer. Therefore, in the present embodiment, the display device having only the first antireflection layer has a plurality of absorption peaks in a wavelength range of about 480nm to about 780nm, and has a transmittance of, for example, about 0.07 to about 0.12.

Referring to fig. 4B, the spectrum diagram shown in fig. 4B is applied to the second antireflection layer. The transmission rates in the spectrogram shown in fig. 4B are normalized. In this embodiment, the second antireflection layer has an absorption peak at a wavelength of about 595nm, and the transmittance of the absorption peak is about 0.20.

Referring to fig. 4C, the spectrum diagram shown in fig. 4C is suitable for the second antireflection layer, the red light emitting device, the green light emitting device and the blue light emitting device. The transmission in the spectrogram shown in fig. 4C is normalized. In this embodiment, the light emitting devices may include a red light emitting device, a green light emitting device and a blue light emitting device. The emission wavelength of the red light-emitting element is, for example, about 630 nm; the emission wavelength of the green light-emitting element is, for example, about 520 nm; the emission wavelength of the blue light emitting element is, for example, about 460 nm. As can be seen from the spectrograms shown in fig. 4B and 4C, the absorption wavelength of the second antireflection layer is, for example, about 590nm to about 600 nm. In other words, the light emitting wavelength of each light emitting element is located outside the range of the absorption wavelength of the second antireflection layer. That is, the second reflection reducing layer of the present embodiment does not substantially absorb the light emitted by the light emitting device, so that even if the light emitting region of the display device is shielded by the second reflection reducing layer, the problem of color shift caused by the light emitted by the light emitting device after penetrating through the second reflection reducing layer can be avoided, and the loss of the transmittance of the light emitted by the light emitting device can also be avoided.

On the other hand, optical simulations were performed on example 1, comparative example 2, and comparative example 3, and the results obtained by the optical simulations are shown in table 1 below, in which example 1 is a display device as shown in fig. 1C, and provided with a first antireflection layer and a second antireflection layer; comparative example 1 is the display device shown in fig. 1A, and the first antireflection layer or the second antireflection layer is not provided; comparative example 2 is a display device as shown in fig. 1B, in which only the first antireflection layer is provided; the display device of comparative example 3 was provided with only the second antireflection layer. The numerical values in parentheses indicate the amount of decrease in reflectance compared to comparative example 1.

[ Table 1]

	x	y	Reflectance (%)	CCT(K)
					Example 1	0.3406	0.3176	10.22(-79.31)	5086
Comparative example 1	0.3076	0.3142	89.53(0)	6948
					Comparative example 2	0.3766	0.3494	15.93(-73.60)	3914
Comparative example 3	0.2280	0.2273	40.63(-48.90)	5213

X and y denote x and y in CIE chromaticity coordinates (x, y) under the condition of D65 illuminant, respectively.

As can be seen from table 1, the display device of example 1 can reduce the reflectance by 79.31% and reduce the Correlated Color Temperature (CCT) from 6948K to 5086K by providing the first antireflection layer and the second antireflection layer, compared to comparative example 1. In addition, although the reflectance of the display device of comparative example 2 is reduced by 73.60% compared to that of comparative example 1, the color temperature of comparative example 2 is 3914K, that is, the color exhibited by the display device of comparative example 2 is yellowish. In addition, although the color temperature of the display device of comparative example 3 was reduced from 6948K to 5213K as compared to comparative example 1, the reflectance value of comparative example 3 was reduced by only 48.90%, i.e., the reflectance reduction of the display device of comparative example 3 was smaller than that of the display device of example 1. Therefore, the display device of embodiment 1 can greatly reduce the reflectance and adjust the color temperature to be within the range of the natural light hue (for example, 5000K to 6000K).

Fig. 5 is a schematic diagram illustrating changes in transmittance and reflectance according to an embodiment of the invention. In this embodiment, a display device provided with a first antireflection layer and a second antireflection layer is taken as an example.

In this embodiment, the concentration of the second antireflection layer can be adjusted. For example, the concentration of the second anti-reflection layer is adjusted from low to high, so that the color of the second anti-reflection layer changes from transparent to bluish and then to blue, and thus the brown reflected light reflected by the first anti-reflection layer changes the obtained hue from brown to white and then to blue after passing through the second anti-reflection layer. That is, the concentration of the second antireflection layer is adjusted to an appropriate concentration, whereby a display device having excellent color characteristics such as hue can be obtained.

On the other hand, the higher the concentration of the second antireflection layer, the lower the reflectance, but the lower the transmittance. For example, a graph of the transmittance and reflectance changes caused by adjusting the concentration of the second antireflective layer is shown in FIG. 5. As can be seen from fig. 5, the lower the reflectance, the lower the transmittance. From the viewpoint of the display effect of the display device, the concentration of the second antireflection layer is preferably adjusted to a concentration at which the reflectance is about 40% and the transmittance is about 80%. Therefore, even if the second antireflection layer shields the light emitting area of the display device, the second antireflection layer can simultaneously have low reflectivity and high transmittance.

In summary, the first anti-reflection layer is disposed to shield a large area of the signal lines, so as to reduce the reflectivity of the display device caused by the exposed signal lines. In addition, the second reflection reducing layer with the absorption wavelength different from that of the first reflection reducing layer is covered on the first reflection reducing layer, so that the reflected light reflected by the first reflection reducing layer can be converted into the reflected light with the hue close to the natural light after penetrating through the second reflection reducing layer, and the display device has low reflectivity and can also present the display effect with excellent color characteristics such as hue and the like. In addition, the absorption wavelength of the second antireflection layer is different from the light-emitting wavelength of the light-emitting element, so that even if the second antireflection layer shields the light-emitting element, the light transmittance of the light-emitting element can be prevented from being reduced.

Although the present invention has been described with reference to the above embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention.

Claims

1. A display device, comprising:

a substrate;

a plurality of scanning lines configured on the substrate and extending along a first direction;

a plurality of data lines disposed on the substrate and extending along a second direction, wherein the first direction intersects the second direction;

a plurality of light emitting elements arrayed on the substrate, each of the light emitting elements being surrounded by two adjacent scan lines and two adjacent data lines, and the light emitting elements being electrically connected to one of the scan lines and one of the data lines;

a first antireflection layer covering the plurality of scanning lines and the plurality of data lines and having a plurality of openings, wherein the plurality of openings expose the light emitting elements; and

a second antireflection layer disposed on the substrate, the second antireflection layer overlapping at least the first antireflection layer in a plan view of the display device,

the light-emitting element has a light-emitting wavelength different from an absorption wavelength of the second antireflection layer, and the first antireflection layer has an absorption wavelength different from an absorption wavelength of the second antireflection layer.

2. The display device of claim 1, wherein the color of the first antireflective layer comprises brown and the color of the second antireflective layer comprises bluish.

3. The display device as claimed in claim 1, wherein the CIE chromaticity coordinates (x, y) of the reflected light reflected by the first antireflection layer satisfy the following formulas (1) and (2) under the condition of D65 light source:

0.350 ≦ x ≦ 0.400 formula (1)

0.350 ≦ y ≦ 0.400 formula (2).

4. The display device according to claim 1, wherein the CIE chromaticity coordinates (x, y) of the reflected light reflected by the first antireflection layer and transmitted through the second antireflection layer satisfy the following formulas (3) and (4) under the condition of the D65 light source:

0.280 ≦ x ≦ 0.350 equation (3)

0.280 ≦ y ≦ 0.350 equation (4).

5. The display device according to claim 1, wherein the absorption wavelength of the second antireflection layer is 590nm to 600nm, and the light transmittance of the second antireflection layer at a wavelength of 590nm to 600nm is 0.30 or less.

6. The display device of claim 1, wherein the second anti-reflective layer is globally over the substrate.

7. The display device of claim 6, wherein the second antireflection layer comprises:

a flat layer disposed on the substrate and covering the first antireflection layer and the light emitting element; and

and an absorption layer disposed on the planarization layer, wherein the absorption layer at least overlaps the first antireflection layer in a plan view of the display device.

8. The display device of claim 6, wherein the second antireflection layer comprises:

and absorbing particles dispersed in the planarization layer.

9. The display device according to claim 1, wherein the first antireflection layer includes a first dielectric layer, a photoresist layer, and a second dielectric layer in this order from the substrate side, the second dielectric layer conformally covering the photoresist layer.

10. The display device according to claim 9, wherein a material of the first dielectric layer and the second dielectric layer is silicon nitride, and a material of the photoresist layer is a positive type photoresist.

11. The display device of claim 1, further comprising:

a plurality of pad patterns arranged on the substrate in an array, wherein at least one of the pad patterns is exposed from one of the openings of the first antireflection layer and is electrically connected with the light emitting element, and wherein

A distance between a sidewall of the one of the plurality of openings extending along the second direction and a side of the exposed pad pattern extending along the second direction is about 10 ± 3% μm.